DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on April 14, 2026 has been entered.
Response to Amendment and Status of Claims
Applicant’s amendments to the claims, filed April 14, 2026, are acknowledged. Claim 1 is amended. Claims 14-15 are cancelled. No new matter has been added.
Claims 3-4 and 17-20 remain withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Invention II, drawn to a dust core and a magnetic component, there being no allowable generic or linking claim. Applicant timely elected without traverse in the reply filed March 4, 2025.
Claims 1-6, 8-13 and 16-20 are pending and Claims 1-2, 5-6, 8-13 and 16 are currently considered in this office action.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 1 rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The term “simple” in Claim 1 is a relative term which renders the claim indefinite. The term “simple” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-2, 8-10, 12-13 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Tsukada (cited by Applicant in IDS filed July 23, 2024, US 5800636 A) in view of Maeda (US 20070235109 A1).
Regarding Claim 1, Tsukada discloses soft magnetic metal particles comprising a core particle and an insulation layer formed on the surface of the core particle (Abstract; Col. 9, 60-Col. 10, line 5; Col. 3, lines 26-28), wherein
a mixture of silica sol, titanium alkoxide and silicone resin is dispersed on the surface of the core particle and cured from 50-250C, resulting in an insulation layer consisting of SiO2 (converted from the silica sol) and TiO2 (converted from titanium alkoxide) within silicone resin (Col. 9, lines 8-12 and 29-31; Col. 9, line 60-Col. 10, line 5, curing to convert to SiO2; curing would convert titanium alkoxide to titanium oxide). Silicone resin (compound) comprising TiO2 (Ti) reads on the broadest most reasonable interpretation of a compound including Ti, as claimed. Additionally, Tsukada teaches the particles are further annealed at 550-650C, which converts the silicone resin to SiO2, and the annealed insulating layer would consist of SiO2 and TiO2, which further reads on the claimed limitations of an insulation layer consisting of a simple substance and/or compound including Ti (TiO2) and SiO2 (Abstract; Fig. 4, annealing at 550-650C).
Tsukada further discloses wherein the insulation layer comprises 15-210ppm Ti and 0.03-0.1wt% Si (Abstract; Col. 2, lines 43-45). One of ordinary skill in the art would appreciate that the disclosed amounts of Si and Ti (0.03-0.1wt% Si and 15-210ppm Ti) refer to the insulating layer because the core is an Fe particle which is not an alloy, and does not comprise Si and Ti.
One of ordinary skill in the art would appreciate that 0.03-0.1wt% Si and 15-210ppm Ti equates to an amount of 0.09-29mol% Ti with respect to a total amount of Si and Ti in the insulation layer, which reads on the claimed range of 1.0-30 mol% Ti.
Additionally, Tsukada discloses working examples which comprise 11.6 mol%, 4.9 mol% and 9.6 mol% Ti with respect to a total amount of Si and Ti in the insulation layer (see Table 1, sample numbers 1-3, which comprise 94ppm, 45ppm and 96ppm (0.0094wt%, 0.0045wt% and 0.0096wt%) Ti and Si contents of 0.042wt%, 0.051wt% and 0.053wt%, respectively, which equates to 11.6 mol%, 4.9mol% and 9.6mol% Ti with respect to a total amount of Si and Ti, as calculated based on molar masses of Si and Ti).
In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). See MPEP § 2144.05.I.
Tsukada fails to disclose a layer other than the insulation layer which exists between the insulation layer and the surface of the core particle, and wherein the layer other than the insulation layer comprises a phosphoric acid compound.
Maeda teaches a two layer insulation coating whereby a first layer of phosphoric acid improves the adhesiveness between the insulation layer and the iron particle, and wherein the second layer, comprising a metal alkoxide, comprises high temperature stability, thereby preventing decomposition of the first insulating coating (para. [0022]). Maeda teaches a coating thickness as low as 5nm in order to effectively suppress energy loss from the eddy current, while maximizing for magnetic flux density (para. [0050]). Maeda also discloses a third layer of silicone resin, or any substance which converts to Si, in order to further insulate the magnetic particles thereby decreasing eddy current loss (para. [0115]; para. [0098]- [0099]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included a phosphoric acid compound coating layer with a thickness as low as 5nm on the surface of the soft magnetic particle, and therefore between the insulation layer (Ti and Si oxide layer) of Tsukada and the surface of the core particle as claimed, as taught by Maeda, for the invention disclosed by Tsukada. One would be motivated to form this insulating layer configuration in order to improve adhesiveness of the insulating layers and the iron particle while providing high temperature stability and preventing decomposition of the first insulation layer, and in order to effectively suppress eddy current loss while maximizing for magnetic flux density (see teachings by Maeda).
Regarding Claim 2, Tsukada discloses wherein the core particle includes Fe (Abstract; Col. 11, line 59-60; Col. 9, lines 60-61).
Regarding Claim 8, Maeda discloses wherein the layer other than the insulation layer comprises a thickness as low as 5nm, which reads on the claimed range of 20nm or less (Maeda, para. [0050]; see teaching above in Claim 1).
Regarding Claim 9, Tsukada discloses wherein the amount ratio of Ti is within a range of 3.0-15mol% with respect to the total amount of Si and Ti in the insulation layer (Table 1, sample numbers 1-3, which comprise 94ppm, 45ppm and 96ppm (0.0094wt%, 0.0045wt% and 0.0096wt%) Ti and Si contents of 0.042wt%, 0.051wt% and 0.053wt%, respectively, which equates to 11.6 mol%, 4.9mol% and 9.6mol% Ti with respect to a total amount of Si and Ti, as calculated based on molar masses of Si and Ti).
Regarding Claim 10, Tsukada discloses wherein the amount ratio of Ti is within a range of 4.0-10mol% with respect to the total amount of Si and Ti in the insulation layer Table 1, sample numbers 2-3, which comprise 45ppm and 96ppm (0.0045wt% and 0.0096wt%) Ti and Si contents of 0.051wt% and 0.053wt%, respectively, which equates to 4.9mol% and 9.6mol% Ti with respect to a total amount of Si and Ti, as calculated based on molar masses of Si and Ti).
Regarding Claim 12, Tsukada discloses wherein the thickness of the insulation layer has a thickness of 50-160m, which reads on the claimed range of 5-500nm (Col. 9, lines 60-62).
Regarding Claim 13, Tsukada discloses wherein the thickness of the insulation layer has a thickness of 50-160m, which reads on the claimed range of 10-200nm (Col. 9, lines 60-62).
Regarding Claim 16, Tsukada discloses curing the Ti alkoxide, and one of ordinary skill in the art would appreciate that the Ti alkoxide would convert to TiO2 after curing, which reads on an oxide of Ti (Abstract; Col. 5, lines 10-13, titanium alkoxides; Fig. 1, curing).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Tsukada (previously cited and cited by Applicant in IDS filed July 23, 2024, US 5800636 A) in view of Maeda (US 20070235109 A1), as applied to Claim 2 above, in further view of Kondo (previously cited, US 20040061582 A1).
Regarding Claim 5, Tsukada discloses wherein the core is an iron particle, but fails to disclose wherein the core particle further includes Si, Ni or Co.
Kondo teaches a pure iron core for a soft magnetic particle covered by an insulating film, wherein the iron particle may also be an alloy of Fe, including other elements such as Si, Ni and Co in order to comprise high magnetic flux density and low coercive force (para. [0040]-[0043]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a Fe-based core particle further comprising Si, Ni and/or Co, as taught by Kondo, for the invention disclosed by Tsukada, in order to achieve high magnetic flux density and low coercive force (see teachings above).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Tsukada (previously cited and cited by Applicant in IDS filed July 23, 2024, US 5800636 A) in view of Maeda (US 20070235109 A1), as applied to Claim 1 above, in further view of Yamamoto (previously cited, JP 2015026661 A, English Machine Translation provided).
Regarding Claim 6, Tsukada discloses wherein the insulation/binding layer covers the particle, but does not expressly disclose the coverage percentage.
Yamamoto teaches wherein the insulation layer covers 100% of the particle in order to improve core loss characteristics (para. [0014]; para. [0025]; para. [0036]; para. [0009]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have comprised 100% coverage of the insulation layer of Tsukada, as taught by Yamamoto, in order to improve core loss characteristics (see teaching above).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Tsukada (previously cited and cited by Applicant in IDS filed July 23, 2024, US 5800636 A) in view of Maeda (US 20070235109 A1), as applied to Claim 1 above, in further view of Ishida (previously cited, US 20170162307 A1).
Regarding Claim 11, Tsukada fails to disclose wherein the insulation layer further includes at least one element selected from the group consisting of Ba, Ca, Mg, Al, Zr, Ni, Mn and Zn, wherein a total amount of ratio of the at least one element is 1 mol% or less with respect to an amount of Ti.
Ishida discloses wherein an insulating film comprises an inorganic oxide, wherein the inorganic oxide is at least one of Mg, Al, Si, Ca, Ti, Zr, and Ba, and is preferably SiO2, TiO2, Al2O3 and ZrO2 in consideration of strength and inherent specific resistance (para. [0066]-[0067]; para. [0073]; para. [0078]). Ishida teaches wherein the metal alkoxides, which form the inorganic oxide, may be used in combination (para. [0080]; para. [0066], wherein alkoxides form the inorganic oxide). Thus, one of ordinary skill in the art would appreciate that Ishida teaches using a combination of the inorganic oxide for the insulation film.
Ishida further teaches wherein the inorganic oxide exists in the insulation layer from 0.01-5wt% with respect to the soft magnetic particle (para. [0067]).
Tsukada discloses up to 0.03-0.1wt% Si in the binder/insulation layer, which exists exclusively as SiO2 (Abstract; see Col. 10, lines 1-4), and therefore one of ordinary skill in the art would appreciate wherein the binder/insulation layer comprises about 0.064-0.21% SiO2 (as calculated from the amount of Si present).
Tsukada also discloses up to 210ppm (Abstract; Col. 2, lines 44-45; Col. 11, lines 47-49; 210ppm is 0.021wt% Ti), and one of ordinary skill in the art would appreciate that up to 1mol% of Zr or up to 1mol% of Al, with respect to the amount of Ti disclosed by Tsukada (up to 210ppm, or 0.021%), would equate to the inclusion of approximately 0.00074wt% ZrO2 or 0.00084% of Al2O3 (calculated based on molar masses of Zr, ZrO2, Al, Al2O3 and Ti).
An amount of SiO2 (0.064-0.21% SiO2 by Tsukada), and the inclusion of up to 0.00074wt% ZrO2 or alternatively of up to 0.00084wt% Al2O3 (from Ishida), is within the range of total inorganic oxide taught by Ishida (0.01-5wt% - see para. [0067]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included up to 0.00074wt% ZrO2 or up to 0.00084wt% Al2O3 in combination with the SiO2 of Tsukada, as taught by Ishida, in order to tailor the inherent specific resistance and the strength of the binder/insulation layer (see teachings by Ishida above), and because these amounts are within the range of total inorganic oxides in the insulation layer allowed by and taught by Ishida.
For an amount of 210ppm (0.021wt% Ti), up to 0.00074wt% ZrO2 or up to 0.00084% of Al2O3 would equate to the inclusion of up to 1mol% of Zr or up to 1mol% of Al with respect to the amount of Ti disclosed by Tsukada, and therefore within the range claimed (see explanation above).
Response to Arguments
Applicant’s arguments, filed April 14, 2026, with respect to Claim 1, and dependent claims thereof, rejected under 35 U.S.C. 103 over Tsukada in view of Hirose, have been fully considered, but are respectfully not found persuasive. Additionally, upon further consideration, the rejection has been withdrawn and a new ground(s) of rejection is made under 35 U.S.C. 103 over Tsukada in view of Maeda, as detailed above.
Regarding Tsukada:
Applicant argues that Tsukada requires silicone resin, which is outside the list of a simple substance of Ti and/or a compound including Ti, and SiO2 and/or a composite oxide which includes Si and other elements.
This argument is not found persuasive.
Silicone resin reads on the broadest most reasonable interpretation of a compound, and currently the claims do not define compound. The Ti and/or TiO2 within the silicone resin therefore reads on a compound (silicone resin) including Ti. Further, Tsukada discloses annealing the particles comprising the insulating layer (see Fig. 1), and one of ordinary skill in the art would appreciate this annealing would convert the silicone resin to SiO2 and therefore the insulating layer after annealing would consist of TiO2 and SiO2, which reads on the claimed limitations as well.
Applicant argues that the soft magnetic particle before compression of the instant invention substantially does not include Si-containing resin and that the iron powder of Tsukada comprising the Si-containing resin is different.
Applicant argues that the soft magnetic particle in the dust core of the instant invention enables Ti present only the insulation layer and not in the grain boundary phase, unlike the invention of Tsukada.
These arguments are not found persuasive.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., features of particles before compression, absence of silicone resin and absence of Ti present in the grain boundary phase) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). The claims do not presently limit the particle to being in powder form, prior to compression, or prior to dust core formation.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Yoshidome (previously cited, US 20190279802 A1): teaches a two-layer coating structure comprising a first inner layer of Fe-based oxide and a second outer layer Si-based oxide (para. [0050]; para. [0065]), wherein the first inner layer of Fe-based oxide is between a Fe-based core particle and the second outer layer, and comprises a thickness of preferably less than 20nm and a dense structure, which allows for the reduction of dielectric breakdown and for enhanced withstand voltage (para. [0062]-[0063]).
Yoshidome further teaches wherein the inner layer advantageously prevents migration of Fe from the soft magnetic particle into the second outer layer Si-based oxide, such that the two-layer structure allows for both high insulation property and good withstand voltage, while improving the resistivity of a dust core manufactured from the soft magnetic metal powder (para. [0071]; para. [0109]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included a Fe-based inner layer of 20nm or less between the iron particle core and SiO2-based insulation layer of Tsukada, as taught by Yoshidome, in order to provide a dense coating structure allowing for the reduction of dielectric breakdown and for enhanced withstand voltage, and in order to improve insulation property and resistivity of a dust core by preventing Fe migration from the iron core to the SiO2-based insulation layer (see teachings above).
Hirose (previously cited, US 20080253917 A1): teaches forming multiple layers on a soft magnetic particle, wherein a first layer on the soft magnetic particle surface formed through a reaction with phosphoric acid, and therefore is a phosphoric acid compound such as phosphates, and wherein an additional, second layer may be one comprising oxides of Ti and Si, and wherein the layers comprise an average thickness of 5-100nm (para. [0047]-[0050]; see para. [0048] wherein insulating films comprise a plurality of layers). One of ordinary skill in the art would appreciate the layer formed through phosphoric acid treatment to be the first layer on the soft magnetic particle (and therefore between the soft magnetic particle and any subsequent layers) in order to react with the phosphoric acid.
Hirose teaches wherein the insulating films serve as an insulating layer and improve the electrical resistance, preventing an eddy current from passing through the iron particles, thereby reducing iron loss (para. [0047]).
Kubota (US 20190333678 A): teaches an insulating coating film comprising a metal alkoxide (para. [0016]; para. [0069]), and further a second insulating coating film between the metal particle and the first insulating coating film, comprising phosphoric acid, in order to prevent reduction in insulation even in the presence of cracking in the outer insulation layer (Abstract; para. [0061]-[0062]).
Yamamoto (previously cited and cited above, JP 2015026661 A, English Machine Translation provided, further teachings): discloses a soft magnetic particle comprising a 1-200nm thick insulating film consisting of oxides of Ti and Si, formed by heat treating a Ti alkoxide and Si alkoxide mixture, wherein the coverage of the metal powder is 100%, and a mol% of Ti by example is 14.97mol% and 19mol% (Abstract; para. [0017]; [0014]-[0015]; para. [0034], coating 6 consists of an oxide of titanium and silicon; Table 1-2, ex. 10 and ex. 29, 0.3 and 0.4 Ti to Si ratio equates to about 14.97mol% and 19mol%, respectively).
Tajima (US 20100266861 A1): teaches forming a separate insulating film of Al-Si-O composite oxide by drying a Si and Al alkoxide mixture at 130-190C for 2 hours, and then coating the composite oxide coating with a silicone resin film, in order to form a uniform silicone resin film by the affinity of the silanol groups of the silicone resin and the SiO2 present on the surface of the alkoxide film, and to form a further insulation film of rigid SiO2 after heat treatment by reaction of the Si in the alkoxide and the silicone resin, thereby increasing heat resistance and enabling high specific resistance (Abstract; para. [0033]; para. [0113]).
Tajima further discloses forming a phosphate type film using phosphoric acid on the surface of the iron particles in order to form the alkoxide film more uniformly with improved adhesivity, thereby improving the specific resistance of the powder magnetic core (para. [0086]-[0088]; para. [0109]-[0110]; para. [0142], phosphoric acid film).
Nakazawa (US 20180068771 A): teaches wherein a powder particle is coated with an alkoxide silane solution and heat treated at 800C to form a SiO2 coating, prior to dust core formation (para. [0125]).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CATHERINE P SMITH whose telephone number is (303)297-4428. The examiner can normally be reached Monday - Friday 9:00-4:00 MT.
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CATHERINE P. SMITH
Patent Examiner
Art Unit 1735
/CATHERINE P SMITH/Examiner, Art Unit 1735
/KEITH WALKER/Supervisory Patent Examiner, Art Unit 1735
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